Diabetes mellitus, glycated haemoglobin and C-peptide levels in relation to pancreatic cancer risk: a study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

AIMS/HYPOTHESIS

There has been long-standing debate about whether diabetes is a causal risk factor for pancreatic cancer or a consequence of tumour development. Prospective epidemiological studies have shown variable relationships between pancreatic cancer risk and blood markers of glucose and insulin metabolism, overall and as a function of lag times between marker measurements (blood donation) and date of tumour diagnosis.

METHODS

Pre-diagnostic levels of HbA(1c) and C-peptide were measured for 466 participants with pancreatic cancer and 466 individually matched controls within the European Prospective Investigation into Cancer and Nutrition. Conditional logistic regression models were used to estimate ORs for pancreatic cancer.

RESULTS

Pancreatic cancer risk gradually increased with increasing pre-diagnostic HbA(1c) levels up to an OR of 2.42 (95% CI 1.33, 4.39 highest [≥ 6.5%, 48 mmol/mol] vs lowest [≤ 5.4%, 36 mmol/mol] category), even for individuals with HbA(1c) levels within the non-diabetic range. C-peptide levels showed no significant relationship with pancreatic cancer risk, irrespective of fasting status. Analyses showed no clear trends towards increasing hyperglycaemia (as marked by HbA(1c) levels) or reduced pancreatic beta cell responsiveness (as marked by C-peptide levels) with decreasing time intervals from blood donation to cancer diagnosis.

CONCLUSIONS/INTERPRETATION

Our data on HbA(1c) show that individuals who develop exocrine pancreatic cancer tend to have moderate increases in HbA(1c) levels, relatively independently of obesity and insulin resistance-the classic and major risk factors for type 2 diabetes. While there is no strong difference by lag time, more data are needed on this in order to reach a firm conclusion.

Immunoregulation effect by overexpression of heme oxygenase-1 on cardiac xenotransplantation

OBJECTIVE

This study was designed to investigate the effect of the overexpression of heme oxygenase-1 (HO-1) on the immunoregulation in the model of abdominal cardiac xenotransplantation from the guinea pig to the rat.

MATERIALS AND METHODS

To increase the expression of HO-1, both donors and recipients were injected with heme through the abdomen before the operation. The donors (guniea pigs) and the recipients (Sprague-Dawley [SD] rats) were divided randomly into three groups: group A, the heart from a guinea pig transplanted into the abdomen of an SD rat; group B, the recipients were injected with Chinese cobra venom factor (CVF) into the abdomen (40 μg/kg and 60 μg/kg 24 hours later) prior to transplantation; group C, CVF + HO-1 high-expression group: donors and recipients were abdominally injected with heme (75 μmol/kg for 2 days before transplantation). The mean survival time (MST), pathological changes, the positive area of HO-1 in the grafted hearts, as well as the expressions of C-C chemokine receptor 5 (CCR5), intercellular adhesion molecule-1 (ICAM-1), and natural killer (NK) cell activity in recipients.

RESULTS

1. The MST was longest in group C treated with heme. 2. The pathologic changes of hyperacute rejection were showed on the donor heart in group A, while delayed xenograft rejection changes took place on donor heart in other groups. 3. Compared with group B, The HO-1 positive area in the donor hearts of group C was significantly higher. (P < .05). 4. The lever of ICAM-1 and CCR5 in the peripheral blood of recipients (pg/mL) was attenuated in group C injected with heme. 5. Compared with group B, the activity of NK cell in the peripheral blood of recipients was much lower in group C (P < .05).

CONCLUSION

The MST was prolonged by increasing expressions of HO-1, but acute vascular rejection was not completely overcome. Activation of vascular endothelial cells could be decreased by strengthening the expression of HO-1. NK cell activity was weakened by reinforced expression of HO-1.

Antibiotics and asthma medication in a large register-based cohort study - confounding, cause and effect

BACKGROUND

An association between asthma and antibiotic usage has been demonstrated, and the issue of reverse causation and confounding by indication is much debated.

OBJECTIVE

Our aim was to study the association between different classes of antibiotics and prescription of asthma medication in a register-based cohort of all Swedish children, born between July 2005 and June 2009, ever treated with antibiotics.

METHODS

Data on dispensed prescriptions of antibiotics (ATC-codes J01) and asthma medication (ATC-codes R03A-D) were requested from the Prescribed Drug Register. The association between dispensed prescriptions of different classes of antibiotics and asthma medication was analysed with Cox regression and a descriptive sequence symmetry analysis.

RESULTS

In total, 211 192 children had received prescriptions of antibiotics. There was a strong association between prescription of antibiotics and prescription of asthma medication. The hazard ratios (HRs) for asthma medication associated with prescription of amoxicillin, penicillin, cephalosporin and macrolides (Gram-positive infections) were stronger than HRs associated with prescription of sulphonamides, trimethoprim and quinolones (urinary tract infections) and flucloxacillin (skin and soft tissue infections), e.g. first year HR = 2.27 (95% confidence intervals 2.17-2.37) as compared with HR = 1.04 (0.78-1.40). The HR associated with broad spectrum antibiotics was significantly higher than the narrow spectrum.

CONCLUSIONS AND CLINICAL RELEVANCE

Our data suggest that the association between antibiotics and asthma is subject to either reverse causation or confounding by indication due to respiratory tract infections. This implies that careful consideration is required as to whether or not symptoms from the respiratory tract in early childhood should be treated with antibiotics or asthma medication.

Hospitalisation of and mortality from bleeding peptic ulcer in Sweden: a nationwide time-trend analysis

BACKGROUND

Time-trend analyses of incidence and mortality in bleeding peptic ulcer show divergent results.

AIM

To conduct a detailed national analysis of hospitalisation of and mortality from bleeding peptic ulcer in Sweden.

METHOD

Data from all hospitalisations at departments with primary responsibility for patients with bleeding ulcer in Sweden, with main diagnosis or co-diagnosis of bleeding ulcer from 1987 to 2005 were retrieved from the Hospital Discharge Register. A validation study was performed due to an uncertainty in diagnostic setting after the introduction of ICD-10 in 1997. Annual hospitalisation rates per 100 000 inhabitants in relation to gender, age and ulcer location were calculated as well as age-standardised 30-day mortality rates.

RESULTS

Hospitalisations for bleeding ulcer decreased from 63.9 to 35.3 per 100 000 inhabitants per year during the study period. The decrease was greater among men (men: from 80.4 to 40.9; women: from 47.7 to 29.7) and in younger age groups. Bleeding gastric ulcer decreased in both genders, and bleeding duodenal ulcer decreased most among men, but was stable in a subgroup of elderly women. Median age increased from 70 to 76 years. Standardised 30-day mortality increased from 5.3% to 6.2%. The increased mortality was found in those aged more than 65 years and with duodenal ulcer disease, whereas mortality remained unchanged in those with bleeding gastric ulcer.

CONCLUSION

Hospitalisation rates for bleeding peptic ulcer have markedly decreased in Sweden in all age groups. The 30-day mortality is low compared with other nationwide studies in the western world, but has increased among patients with duodenal ulcer disease.

Assessment of cell proliferation and muscular structure following surgical tongue volume reduction in pigs

OBJECTIVES

Tongue volume reduction is an adjunct treatment in several orofacial orthopaedic procedures for various craniofacial deformities; it may affect structural reconstitution and functional recovery as a result of the repair process. The aim of this study was to investigate myogenic regeneration and structural alteration of the tongue following surgical tongue volume reduction.

MATERIALS AND METHODS

Five 12-week-old sibling pairs of Yucatan minipigs (three males and two females) were used. Midline uniform glossectomy was performed on one of each pair (reduction); siblings had identical incisions without tissue removal (sham). All pigs were raised for a further 4 weeks and received 5-bromo-2-deoxyuridine (BrdU) injection intravenously 1 day before killing. Tissue sections of tongues were stained with anti-BrdU antibody to evaluate numbers of replicating cells. Haematoxylin and eosin plus trichrome staining were performed to assess muscular structure.

RESULTS

Reduction tongues contained significantly more BrdU+ cells compared to sham tongues (P < 0.01). However, these BrdU+ cells were mostly identified in reparative connective tissues (fibroblasts) rather than in regenerating muscle tissue (myoblasts). Trichrome-stained sections showed disorganized collagen fibres linked to few intermittent muscle fibres in the reduction tongues. These myofibres presented signs of atrophy with reduced perimysium and endomysium. Matrix between reduced perimysium and endomysium was filled with fibrous tissue.

CONCLUSIONS

Fibrosis without predominant myogenic regeneration was the major histological consequence of surgical tongue volume reduction.

An estimate of amyotrophic lateral sclerosis heritability using twin data

BACKGROUND

Causative gene mutations have been identified in about 2% of those with amyotrophic lateral sclerosis (ALS), often, but not always, when there is a strong family history. There is an assumption that there is a genetic component to all ALS, but genome-wide association studies have yet to produce a robustly replicated result. A definitive estimate of ALS heritability is therefore required to determine whether ongoing efforts to find susceptibility genes are worth while.

METHODS

The authors performed two twin studies, one population- and one clinic-based. The authors used structural equation modelling to perform a meta-analysis of data from these studies and an existing twin study to estimate ALS heritability, and identified 171 twin pairs in which at least one twin had ALS.

RESULTS AND DISCUSSION

Five monozygotic twin pairs were concordant-affected, and 44 discordant-affected. No dizygotic twin pairs were concordant-affected, and 122 discordant-affected. The heritability of sporadic ALS was estimated as 0.61 (0.38 to 0.78) with the unshared environmental component 0.39 (0.22 to 0.62). ALS has a high heritability, and efforts to find causative genes should continue.

Discovery of notch-sparing gamma-secretase inhibitors

Overwhelming evidence supports a central role for the amyloid beta-peptide (Abeta) in the pathogenesis of Alzheimer's disease (AD), and the proteases that produce Abeta from its precursor protein APP are top targets for therapeutic intervention. Considerable effort has focused on targeting gamma-secretase, which generates the C-terminus of Abeta; however, gamma-secretase inhibitors cause serious toxicities due to interference with the Notch signaling pathway. We have been working toward compounds that directly alter gamma-secretase activity to reduce Abeta production without affecting the proteolysis of Notch. Using purified enzyme and substrate, we have shown that gamma-secretase can be selectively inhibited in this way by naphthyl-substituted gamma-aminoketones and gamma-aminoalcohols. These early hits, however, suffered from chemical instability and/or poor potency. Iterative design, synthesis and evaluation have led to the discovery of Notch-sparing gamma-secretase inhibitors with substantially increased potencies in biochemical and cellular assays. These compounds are of low molecular weight and are under evaluation for drug-like properties. The discovery and development of these compounds will be discussed.

First Record of Trichodorus primitivus and Morphological and Molecular Identification of Longidorus elongatus from Canada

During July 2008, sandy loam soil samples were collected near the rhizosphere of Kentucky bluegrass (Poa pratensis L.) and tall fescue (Festuca arundinacea Schreb.) at a depth of 15 to 20 cm from Caledonia Park, Toronto, Canada. Samples were suspended in water and nematodes were collected on sieves with 250- and 74-μm openings. Among the nematodes recovered were one species of Longidorus Micoletzky, 1922 (4) and one species of Trichodorus Cobb, 1913. The Trichodorus species (2), was identified as T. primitivus (de Man, 1880) Micoletzky, 1922, in which females have rod-like sclerotized pieces parallel to the vagina lumen, each with dimensions of 3.1 × 1.2 μm and at a distance of 2 to 3 μm from each other; and males have spicules with a wide nonoffset capitulum and very narrow blade, three ventromedian cervical papillae (CP), and three precloacal supplements with the anterior one at the level of the capitulum of retracted spicules. Males showed unusual variation in the position of CP2 (i.e., posterior to the onchiostyle region, except for one specimen with CP2 located within the posterior onchiostyle region, which is typical for the species). The morphometric data for nine males are: L, 665 to 805 μm; a, 23.0 to 27.5; b, 3.7 to 5.2; c, 46 to 56; onchiostyle, 47 to 52 μm; and spicules, 32.5 to 40.5 μm. Measurements for 13 females are: L, 630 to 775 μm; a, 20.5 to 24.8; b, 3.5 to 5.5; c, 75.5 to 158.5; and V, 54 to 61%. To our knowledge, this is the first report of T. primitivus in Canada. According to Chen et al. (1), the Longidorus species was identified as L. elongatus (de Man, 1876) Micoletzky, 1922 (3). The morphometric data for females (n = 13) are: L, 5.1 to 6.0 mm; a, 78.5 to 106.5; b, 11.5 to 13.5; c, 86.0 to 120.5; V, 45.5 to 53.0%; odontostyle, 79 to 91 μm; odontophore, 57.5 to 66.5 μm; and tail length, 44.5 to 59.0 μm. Males were not found. Four juvenile stages were identified. J1 (n = 2) with a body length of 1.1, 1.2 mm and replacement/functional odontostyle 59, 59/53.5, 54.5 μm, J2 (n = 2) with L: 1.7, 2.0 mm and replacement/functional odontostyle 62.5, 68.0/58.7 μm, 59.0, J3 (n = 2): L: 2.8, 3.0 mm and replacement/functional odontostyle 76.5, 77/66.5, 67.0 μm and J4 (n = 2) with L: 3.6, 3.8 mm and replacement/functional odontostyle 87.0, 90.5/75.0, 77.5 μm. Due to large morphometric overlap in Longidorus species identification, 2,472 bp of the near full-length 18S and the internal transcribed spacer 1 region of rDNA (Accession No. GU199044) were sequenced. The Blastn search of the partial 18S revealed 100% identity with a population of L. elongatus from Scotland (GenBank No. AY687992, 1,707 bp compared), 99% identity (3 bp difference, 1,707 bp compared) with a population of L. elongatus from Iran (EU503141) and 99% identity (4 bp difference, 1,707 bp compared) with a population of L. elongatus (AF036594, sample location unknown). A Blastn search of the 18S and ITS region revealed only 1 to 3 bp differences with two populations of L. elongatus from Switzerland (AJ549986 and AJ549987) and a population of L. elongatus (AF511417) from Scotland. These molecular data further confirmed the identity of the population from Canada to be L. elongatus. References: (1) Q. Chen et al. Fundam. Appl. Nematol. 20:15, 1997. (2) W. Decraemer. Kluwer Academic Publishers, Dordrecht, the Netherlands, 1995. (3) J. G. de Man. Tijdschr. Ned. Dierk. Ver. 2:78, 1876. (4) H. Micoletzky. Archiv. Naturgesch. 87:1, 1922.

Pharmacokinetics of methyl protodioscin in rats

Methyl protodioscin (MPD), a natural furostanol saponin, showed distinct antitumor activity and is distributed in many traditional Chinese medicines. The pharmacokinetics, distribution and excretion of MPD were first investigated after i.v. injection to rats in this study. The dose-dependent pharmacokinetics of MPD were characterized after i.v. injection (20, 40 and 120 mg/kg of MPD) to rats. A good linearity (r = 0.9989, P < 0.05) was found in the regression analysis of the AUC0-t -dose. The plasma concentrations of MPD declined rapidly with an elimination half-life (t1/2) from 25.56 to 29.32 min. The MPD kinetics was in line with one-compartment model after i.v. injection. 23.43% and 32.86% of MPD was recovered in urine and bile, respectively. The concentrations of MPD in plasma and most examined tissues 5 h after injection were close to or below the Low Limit of Quantification (LLOQ). This indicated that MPD was distributed and eliminated rapidly in rats.

Longitudinal cognitive decline is associated with fibrillar amyloid-beta measured by [11C]PiB

OBJECTIVE

To investigate whether longitudinal declines in cognition are associated with higher fibrillar amyloid-beta (Abeta) deposition in vivo in individuals without dementia.

METHOD

[(11)C]PiB images were obtained to measure fibrillar Abeta burden in 57 participants without dementia from the Baltimore Longitudinal Study of Aging. Participants (33 men, 24 women) had a mean (SD) age of 78.7 (6.2) years. Six participants (4 men, 2 women) had mild cognitive impairment defined as Clinical Dementia Rating = 0.5. To measure [(11)C]PiB retention, distribution volume ratios (DVR) for 15 regions of interest were estimated by fitting a simplified reference tissue model to the measured time activity curves. Mixed effects regression was used to predict cognitive trajectories over time using data before and including time of PiB (mean follow-up 10.8 years), with mean cortical DVR, age at baseline, sex, and education as independent predictors. Voxel-based analysis identified local associations.

RESULTS

[(11)C]PiB retention was higher in older individuals. Greater declines over time in mental status and verbal learning and memory, but not visual memory, were associated significantly with higher PiB retention. Voxel-based analysis showed significant associations in frontal and lateral temporal regions.

CONCLUSIONS

Higher Abeta deposition is associated with greater longitudinal decline in mental status and verbal memory in the preceding years. The differential association for verbal but not visual memory may reflect the greater reliance of verbal word list learning on prefrontal regions, which show early Abeta deposition. Prospective imaging may help distinguish between individuals with evolving neuropathology who develop accelerated cognitive decline vs those with normal aging.

(-)-Gossypol containing hen sera and a myosin (-)-gossypol conjugate reduces the proliferation of MCF-7 cells

Sera from chickens that consumed a known level of (-)-gossypol (-)-GP) exhibited bioactivity against human breast cancer cells in vitro. Based on this, it is conceivable that similar anti-breast cancer activities of different magnitudes will be exhibited in biological samples harvested from (-)-GP-fed layer hens. The experimental data generated in this study may influence the fundamental thinking regarding the utilization of low cost agricultural commodities such as (-)-GP cottonseed meal to produce value-added chemopreventive animal products.

Change of cholinergic transmission and memory deficiency induced by injection of beta-amyloid protein into NBM of rats

The change of cholinergic transmission of beta-amyloid protein (beta-AP) treated rats was studied by intracerebral microdialysis sampling combined with HPLC analysis. beta-AP(1-40) was injected into nucleus basalis magnocellularis (NBM). Passive avoidance response test (step-down test) and delayed alternation task were used for memory testing. The impairment of memory after injection of beta-AP(1-40) into NBM exhibited mainly the deficiency of short-term working memory. One week after injection of beta-AP(1-40) the release of acetylcholine (ACh) from frontal cortex of freely-moving rats decreased significantly, and the response of cholinergic nerve ending to the action of high [K(+)] solution was rather weak. In control animals the percentage of increase of ACh-release during behavioral performance was 57%, while in beta-AP(1-40)-treated rats it was 34%. The temporary increase of the ACh-release of the rat put into a new place was also significantly diminished in beta-AP(1-40) -treated rats. The results show that the injection of beta-AP(1-40) into NBM impairs the cholinergic transmission in frontal cortex, and the impairment of cholinergic transmission may be the main cause of the deficit of working memory.

The Association of Dysglycaemia and Cardiovascular Disease in Patients with Metabolic Syndrome

The objective of this study was to investigate the relationship between increased prevalence of cardiovascular disease and glucose regulation status in Chinese patients with metabolic syndrome (MetS). All patients underwent an oral glucose tolerance test (2-h post-load plasma glucose) to determine their glucose regulation status and had their brachial–ankle pulse wave velocity (baPWV) measured. Of the 590 patients included in the study, 115 (19.5%) had normal glucose tolerance, 114 (19.3%) had impaired fasting glucose (IFG) alone, 38 (6.4%) had impaired glucose tolerance (IGT) alone, 197 (33.4%) had diabetes mellitus and 126 (21.4%) had combined glucose intolerance (CGI; IFG plus IGT). Patients with diabetes mellitus had a significantly higher baPWV compared with all other groups and patients with CGI had a significantly higher baPWW compared with patients with IFG. Dysglycaemia was common in patients with MetS. An increased prevalence of cardiovascular disease in patients with MetS was related to their glucose regulation status.

Healthcare charges and utilization associated with diabetic neuropathy: impact of Type 1 diabetes and presence of other diabetes-related complications and comorbidities

AIMS

The aim was to examine the impact of Type 1 diabetes and having any other diabetes-related complication or comorbidity on healthcare charges and utilization in patients with diabetic neuropathy (DN).

METHODS

We selected individuals aged < 65 years who continuously enrolled in a large US commercial plan from July 2004 to June 2006 and who received at least one diagnosis of DN at any time from July 2004 to June 2005. We compared the prevalence of other diabetes-related complications or comorbidities between patients with Type 1 and with Type 2 diabetes. In patients with DN with or without any other diabetes-related complication or comorbidity, we used multivariate regression to assess the marginal contribution of Type 1 diabetes on healthcare charges and utilization from July 2005 until June 2006.

RESULTS

The majority of DN patients had at least one other diabetes-related complication or comorbidity. Most of the DN patients had Type 2 diabetes. DN patients with Type 1 diabetes had more comorbid medical conditions than those with Type 2 diabetes. Compared with Type 2, Type 1 patients had a higher prevalence of each individual non-DN diabetes-related complication or comorbidity, except heart disease. Controlling for comorbidities, Type 1 and Type 2 patients with DN but no other diabetes-related complication or comorbidity had similar healthcare utilization. However, Type 1 patients had significantly higher charges than those with any other diabetes-related complication or comorbidity.

CONCLUSIONS

Many patients with DN have Type 1 diabetes and other common diabetes-related complications or comorbidities, which can have a significant impact on healthcare charges and utilization.